WATER SENSITIVE URBAN DESIGN & CONSTRUCTED WETLANDS
IN-LINE PRIMARY TREATMENT SOLUTION
The range of Ecosol Silt Arrestors provide a purpose designed and built underground storage pit where water that is contaminated with suspended sediment.
Suspended solids (silt and sediment) from surface run-off are conveyed to the Ecosol Silt Arrestor typically by a conventional drainage pipe. Once trapped within the unit internal baffles slow the flow velocities thereby providing gravitational separation of fine particles entrained within the stormwater flows. Filtered stormwater is then discharged via the outlet pipe back into the drainage network with the solids settled and retained at the base of the unit.
The grading of suspended sediments entering the Silt Arrestor is important in determining settling velocities and to assist you in determining the appropriately sized Silt Arrestor for your project the estimated standard settling time of particles ranging from 0.07 – 0.20mm is approximately 5 – 10 minutes. As a guide, traditionally larger units are typically installed in industrial environments where the smaller 1,600 & 4,000, Ecosol Silt Arrestors would normally be used in small commercial applications such as wash down bays with significantly smaller catchment areas.
SILT ARRESTOR KEY FEATURES AND BENEFITS
Cost efficient and effective primary treatment solution
Visually unobtrusive, fully self-contained underground system
Easily maintained by vacuum truck
Durable, robust product, engineered for the environment in which it operates
At Ecosol we can site measure, fabricate, install and maintain your Silt Arrestor making the whole process seamless.
The Ecosol Silt Arrestor will treat 100% of all flows and have a holding capacity commensurate with the inlet pipe diameter and flows likely to be delivered to the system. The following table shows the Ecosol Silt Arrestors dimensions and holding capacities for typical cylindrical pipe applications.
Ecosol SILT ARRESTOR SYSTEM DESIGNED TREATABLE FLOW RATES
Ecosol Silt Arrestor Product Code
Inlet Pipe Diameters (mm)
Treatable Flow Rates (L/s)
Maximum By-pass Capacity (L/s)
Ecosol Silt Arrestor System Designed Treatable Flow Rates - 2018
To design a system suitable for your project it is necessary to review the configuration of the stormwater system, the catchment area and hydrology. Please consult with your local Ecosol representative for confirmation of preferred system sizes for your project.
Designed Treatable Flow Rate
This is the maximum rate of flow that the Ecosol Silt Arrestor shall receive to enable sufficient gravitational separation to occur and also to prevent resuspending already captured settled solids.
It is recommended that the units designed by-pass capacity is equivalent to the units designed treatable flow rate as this prevents the re-suspension of settled material. The Maximum by-pass capacities quoted above have been provided as an indicative guide only to assist with the overall drainage design.
Industry testing of typical silt arrestors (also known as gravity separators) indicates that they can remove between 50% and 60% of Total Suspended Solids (TSS) down to 10 micron when the system is appropriately sized allowing for sufficient particle settling times within the device.
It is therefore important to appropriately size your device relevant to rainfall intensities and catchment area. The effective capture of TSS also results in the capture of attached particulates.
One of the key advantages of the Ecosol Silt Arrestor systems is that the units are easily cleaned from the surface by vacuum truck. This eliminates any risks associated with manually handling captured pollutants or confined space access. The key benefit of this system is its low capital cost along with its low ongoing cleaning and maintenance cost.
It is recommended that your Ecosol Silt Arrestor is regularly cleaned out of all sediment and at a minimum should be cleaned before the silt level reaches 70% of its designed holding capacity. Cleaning is by vacuum method using commercial vacuum trucks. Cleaning of the unit is completed from the surface level by moving the snorkel over the retained silts and sediment.